1. Field of the Invention
The present invention relates to a system for determining vendibility in automatic vending machines. More specifically, the present invention relates to an improvement in such a system for determining vendibility in automatic vending machines wherein coins inserted by a customer are adapted for use as change for enhancement of the rate of operation of the machines.
2. Description of the Prior Art
Various types of automatic vending machines have been put in practical use. Most of such automatic vending machines are adapted to receive a predetermined plurality of kinds of coins and thus are provided with a coin sorter for sorting these received coins. Sorted coins are each transferred along the respective transport paths which are individually connected to the respective reservoir pipes. Such reservoir pipes for the respective sorted coins are each adapted to receive and stock a predetermined number of coins, while an excess number of coins are adapted to be overflowed. Those coins received and stocked in the reservoir pipe are withdrawn by way of payment of change caused by vending or repayment of money commensurate with the amount received, as the case may be. Such a reservoir pipe is provided with a detecting switch for detecting the presence or absence of the coins stocked therein. If and when the coins stocked in the reservoir pipe have run out, a "run out" signal is generated to inform that coins for change have run out.
In the prior art, if and when such a "run out" signal is generated from a change coin dispensing apparatus in the automatic vending machines, the machines were controlled not to receive any more coins for the purpose of automatic vending, whereby further automatic vending was prevented. As a result, the rate of operation of the prior art automatic vending machines was poor.
In order to improve the rate of operation, an approach was adopted wherein in response to such a "run out" signal, the automatic vending machines were controlled to prevent only that kind of automatic vending which requires change, while the machines were left in an "allowed" condition so as to be permitted to perform that kind of automatic vending that does not require any change. According to this approach, it is necessary for the machine to determine whether the amount of inserted coins coincides with the price of the commodity to be vended, so that a reply signal may be generated for repayment of the inserted coins in case of incoincidence. Although this approach has improved the rate of operation of the automatic vending machines to some extent, there is still room for improvement of the rate of the operation. For example, it could happen that, if the inserted coins had been adapted to be used for change, then the commodity could have been vended automatically, depending upon the price of the commodity being vended. Thus, provision of a scheme for determining whether automatic vending is possible for vendibility is found when the inserted coins are adapted to be appropriated for change might enhance the rate of the operation of the automatic vending machines.